US4533532A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Carboxylic acid activated dry calcium absorbent method for removing sulfur dioxide from a flue gas
Assignee: RWE AG
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Filing: 1984-07-02
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Granted: 1985-08-06
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Expires: 2004-07-02
Abstract
Abstract An absorbent for the dry removal of sulfur dioxide and other noxious and toxic components from a combustion flue gas which consists essentially of at least one finely divided alkaline-earth compound and an additive selected from the group which consists of at least one carboxylic acid or an alkali metal, alkaline-earth metal or ammonium salt thereof.
Inventors
- 👤 Georg R. U. Gebhard
- 👤 Klaus R. G. Hein
- 👤 Wolfgang Glaser
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 04:20
CPC Classifications
B; B01; B01D; B01D53/00; B01D53/34; B01D53/46; B01D53/48; B01D53/50; B01D53/508
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
144 words
A method of removing sulfur dioxide and other noxious and toxic components from the flue gas of a power plant boiler which comprises the steps of: (a) forming an absorbent by intimately mixing at least one alkaline-earth compound capable of absorbing sulfur dioxide with 0.1 to 10 mol % of an additive consisting of at least one absorbent-reactivity promoting carboxylic acid or an alkali metal, alkaline-earth metal or ammonium salt thereof; (b) forming the flue gas by combustion of a fuel in a power plant boiler; (c) contacting the flue gas after its formation in said boiler at an elevated temperature with absorbent formed in step (a) in a dry state and added to said flue gas independently of said combustion; and (d) dry separating the absorbent after it has contacted the flue gas in step (c) from the remainder of the flue gas.
Claim 2
Independent Claim
144 words
A method of removing sulfur dioxide and other noxious and toxic components from the flue gas of a power plant boiler which comprises the steps of: (a) forming an absorbent by intimately mixing at least one alkaline-earth compound capable of absorbing sulfur dioxide with 0.1 to 10 mol % of an additive consisting of at least one absorbent-reactivity promoting carboxylic acid or an alkali metal, alkaline-earth metal or ammonium salt thereof; (b) forming the flue gas by combustion of a fuel in a power plant boiler; (c) contacting the flue gas after its formation in said boiler at an elevated temperature with absorbent formed in step (a) in a dry state and added to said flue gas independently of said combustion; and (d) dry separating the absorbent after it has contacted the flue gas in step (c) from the remainder of the flue gas.
Claim 3
Dependent Claim
13 words
The method defined in claim 1 wherein said alkaline-earth compound is calcium carbonate.
Claim 4
Dependent Claim
18 words
The method defined in claim 2 wherein said absorbent contains 0.1 to 5 mol % of acetic acid.
Claim 5
Independent Claim
115 words
The method of removing sulfur dioxide and other noxious and toxic components from a flue gas of a power plant boiler which comprises the steps of: (a) forming an absorbent by intimately mixing at least one alkaline-earth compound capable of absorbing sulfur dioxide with 0.1 to 10 mol % of an additive consisting of acetic acid or an alkaline metal, alkaline-earth metal or ammonium salt thereof; (b) contacting the flue gas after its formation by combustion and in a drying state to an elevated temperature with the absorbent formed in step (a); and (c) dry separating the absorbent after it has contacted the flue gas in step (c) from the remainder of said flue gas.
Claim 6
Independent Claim
115 words
The method of removing sulfur dioxide and other noxious and toxic components from a flue gas of a power plant boiler which comprises the steps of: (a) forming an absorbent by intimately mixing at least one alkaline-earth compound capable of absorbing sulfur dioxide with 0.1 to 10 mol % of an additive consisting of acetic acid or an alkaline metal, alkaline-earth metal or ammonium salt thereof; (b) contacting the flue gas after its formation by combustion and in a drying state to an elevated temperature with the absorbent formed in step (a); and (c) dry separating the absorbent after it has contacted the flue gas in step (c) from the remainder of said flue gas.
Claim 7
Dependent Claim
13 words
The method defined in claim 4 wherein said alkaline-earth compound is calcium carbonate.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1988-08-05 | 1989-02-04 | 1989-08-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-08-05 | 1993-02-04 | 1993-08-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-08-05 | 1997-02-04 | 1997-08-06 | $7700.00 | Window Closed / Lapsed |